Electric machine with a closed coolant circuit, in particular for driving a vehicle
An electric machine with a housing, a rotor with a rotor cooling channel, and a stator with stator cooling channels. The housing has a distribution system for guiding a coolant flow from the rotor cooling channel to the stator cooling channels.
1 . An electric machine comprising:
a housing,
a rotor with a rotor cooling channel, and
a stator with stator cooling channels,
the housing having a distribution system for guiding a coolant flow from the rotor cooling channel to the stator cooling channels,
wherein a collecting area for collecting the coolant flow exiting from the rotor cooling channel is provided, the housing further having a forwarding channel for guiding the coolant flow from the collecting area to the stator cooling channels,
wherein a coolant inlet for guiding a coolant flow into the rotor cooling channel is provided,
wherein the coolant inlet, the collecting area, and the forwarding channel are formed in a coolant cap which constitutes an axial end part of the housing,
wherein the coolant cap carries a bearing for a shaft of the rotor,
wherein the rotor cooling channel is provided within a rotor shaft,
wherein one axial end of the rotor cooling channel is closed,
wherein the coolant inlet is formed by a projection which extends into the rotor coolant channel,
wherein the coolant cap comprises a central cavity in which an open axial end of the rotor shaft is arranged, the coolant cap comprising the projection and forming the collecting area, and
wherein the coolant cap is a monolithic unitary structure.
2 . The electric machine of claim 1 , wherein the coolant cap is made from metal.
3 . The electric machine of claim 1 , wherein the central cavity receives a coolant guiding element having the projection.
4 . The electric machine of claim 1 , wherein the rotor cooling channel, the collecting area, the forwarding channel and the stator cooling channels are connected in series so as to receive the entire coolant flow.
5 . The electric machine of claim 1 , wherein the stator is formed from stator windings and a carrier element, the stator cooling channels extending in an axial direction along the outer surface of the carrier element.
6 . The electric machine of claim 5 , wherein coolant exiting from axial ends of the stator cooling channels is guided onto axial ends of the stator winding.
7 . The electric machine of claim 6 , wherein the coolant that is guided onto the axial ends of the stator winding is collected in a sump at a bottom of the housing.